套管钻井用套管外表面磨损后剩余强度分析

在分析讨论套管钻井管柱磨损形态的基础上,结合API5C5实物试验尺寸要求,通过有限元计算分析方法,对钻井套管完钻后含有外表面磨损缺陷的套管柱的极限剩余抗挤强度和极限剩余抗拉强度进行了研究,分别获得了均匀磨损和偏磨条件下,套管钻井套管柱外表面磨损缺陷的临界长度尺寸数值,以及不同破坏失效准则条件下的剩余抗挤强度和剩余抗拉强度的计算方程,为套管钻井中套管柱的设计、计算奠定了理论基础。

Analysis on residual strength after casing surface wear caused in casing drilling

On the basis of discussing the shape of casing string wear caused in casing drilling and in combination with the requirements of full size test of API 5C5, the ultimate residual collapse strength and ultimate residual tensile strength ofdrilling casing string (after drilling is completed) with external wear defects are studied by using the method of finite element analysis. The size of critical length of surface wear defects of drill casing strings induced under the conditions of even wear and deviated wear and equations for calculating residual collapse strength and residual tensile strength under different conditions of destructive failure rules are respectively obtained, by which theoretical basis is provided for the design and calculation of drill casing strings.